cwinging / nuster

A high performance HTTP proxy cache server and RESTful NoSQL cache server based on HAProxy

nuster

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A high performance HTTP proxy cache server and RESTful NoSQL cache server based on HAProxy.

Table of Contents

• Introduction
• Performance
• Getting Started
• Usage
• Directives
• Cache
  • Management
  • Enable/Disable
  • TTL
  • Purging
  • Stats
• NoSQL
  • Set
  • Get
  • Delete
• FAQ

Introduction

nuster is a high performance HTTP proxy cache server and RESTful NoSQL cache server based on HAProxy. It is 100% compatible with HAProxy, and takes full advantage of the ACL functionality of HAProxy to provide fine-grained caching policy based on the content of request, response or server status.

Features

As HTTP/TCP loader balancer

nuster can be used as an HTTP/TCP load balancer just like HAProxy.

• All features of HAProxy are inherited, 100% compatible with HAProxy
• Load balancing
• HTTPS supports on both frontend and backend
• HTTP compression
• HTTP rewriting and redirection
• HTTP fixing
• HTTP2
• Monitoring
• Stickiness
• ACLs and conditions
• Content switching

As HTTP cache server

nuster can also be used as an HTTP proxy cache server like Varnish or Nginx to cache dynamic and static HTTP response.

• All features from HAProxy(HTTPS, HTTP/2, ACL, etc)
• Extremely fast
• Powerful dynamic cache ability
  • Based on HTTP method, URI, path, query, header, cookies, etc
  • Based on HTTP request or response contents, etc
  • Based on environment variables, server state, etc
  • Based on SSL version, SNI, etc
  • Based on connection rate, number, byte, etc
• Cache management
• Cache purging
• Cache stats
• Cache TTL

As RESTful NoSQL cache server

nuster can also be used as a RESTful NoSQL cache server, using HTTP POST/GET/DELETE to set/get/delete Key/Value object.

It can be used as an internal NoSQL cache sits between your application and database like Memcached or Redis as well as a user facing NoSQL cache that sits between end user and your application. It supports headers, cookies, so you can store per-user data to same endpoint.

• All features from HAProxy(HTTPS, HTTP/2, ACL, etc)
• Conditional cache
• Internal KV cache
• User facing RESTful cache
• Support any kind of data
• Support all programming languages as long as HTTP is supported

Performance

nuster is very fast, some test shows nuster is almost three times faster than nginx when both using single core, and nearly two times faster than nginx and three times faster than varnish when using all cores.

See detailed benchmark

Getting Started

Download

Download stable version from Download page for production use, otherwise git clone the source code.

Build

make TARGET=linux2628 USE_LUA=1 LUA_INC=/usr/include/lua5.3 USE_OPENSSL=1 USE_PCRE=1 USE_ZLIB=1
make install PREFIX=/usr/local/nuster

use USE_PTHREAD_PSHARED=1 to use pthread lib

omit USE_LUA=1 LUA_INC=/usr/include/lua5.3 USE_OPENSSL=1 USE_PCRE=1 USE_ZLIB=1 if unnecessary

See HAProxy README for details.

Create config file

A minimal config file: nuster.cfg

global
    nuster cache on data-size 100m uri /_nuster
    nuster nosql on data-size 200m
defaults
    mode http
frontend fe
    bind *:8080
    #bind *:4433 ssl crt example.com.pem alpn h2,http/1.1
    use_backend be2 if { path_beg /_kv/ }
    default_backend be1
backend be1
    nuster cache on
    nuster rule img ttl 1d if { path_beg /img/ }
    nuster rule api ttl 30s if { path /api/some/api }
    server s1 127.0.0.1:8081
    server s2 127.0.0.1:8082
backend be2
    nuster nosql on
    nuster rule r1 ttl 3600

nuster listens on port 8080 and accepts HTTP requests. Requests start with /_kv/ go to backend be2, you can make POST/GET/DELETE requests to /_kv/any_key to set/get/delete K/V object. Other requests go to backend be1, and will be passed to servers s1 or s2. Among those requests, /img/* will be cached for 1 day and /api/some/api will be cached for 30 seconds.

Start

/usr/local/nuster/sbin/nuster -f nuster.cfg

Docker

docker pull nuster/nuster
docker run -d -v /path/to/nuster.cfg:/etc/nuster/nuster.cfg:ro -p 8080:8080 nuster/nuster

Usage

nuster is based on HAProxy, all directives from HAProxy are supported in nuster.

Basic

There are four basic sections: global, defaults, frontend and backend as you can find out in above config file.

• global
  • defines process-wide and often OS-specific parameters
  • nuster cache on or nuster nosql on must be declared in this section in order to use cache or nosql functionality
• defaults
  • defines default parameters for all other frontend, backend sections
  • and can be overwritten in specific frontend or backend section
• frontend
  • describes a set of listening sockets accepting client connections
• bankend
  • describes a set of servers to which the proxy will connect to forward incoming connections
  • nuster cache on or nuster nosql on must be declared in this section
  • nuster rule must be declared here

You can define multiple frontend or backend sections. If nuster cache|nosql off is declared or no nuster cache|nosql on|off declared, nuster acts just like HAProxy, as a TCP and HTTP load balancer.

Although listen is a complete proxy with its frontend and backend parts combined in one section, you cannot use nuster in listen, use frontend and backend pairs.

You can find HAProxy documentation in /doc, and Online HAProxy Documentation

As TCP loader balancer

frontend mysql-lb
   bind *:3306
   mode tcp
   default_backend mysql-cluster
backend mysql-cluster
   balance roundrobin
   mode tcp
   server s1 10.0.0.101:3306
   server s2 10.0.0.102:3306
   server s3 10.0.0.103:3306

As HTTP/HTTPS loader balancer

frontend web-lb
   bind *:80
   #bind *:443 ssl crt XXX.pem
   mode http
   default_backend apps
backend apps
   balance roundrobin
   mode http
   server s1 10.0.0.101:8080
   server s2 10.0.0.102:8080
   server s3 10.0.0.103:8080
   #server s4 10.0.0.101:8443 ssl verify none

As HTTP cache server

global
    nuster cache on data-size 200m
frontend fe
    bind *:8080
    default_backend be
backend be
    nuster cache on
    nuster rule all
    server s1 127.0.0.1:8081

As RESTful NoSQL cache server

global
    nuster nosql on data-size 200m
frontend fe
    bind *:8080
    default_backend be
backend be
    nuster nosql on
    nuster rule r1 ttl 3600

Directives

global: nuster cache|nosql

syntax:

nuster cache on|off [data-size size] [dict-size size] [purge-method method] [uri uri]

nuster nosql on|off [data-size size] [dict-size size]

default: none

context: global

Determines whether to use cache/nosql or not.

A memory zone with a size of data-size + dict-size will be created.

Except for temporary data created and destroyed within request, all cache related data including http response data, keys and overheads are stored in this memroy zone and shared between all processes. If no more memory can be allocated from this memory zone, new requests that should be cached according to defined rules will not be cached unless some memory are freed. Temporary data are stored in a memory pool which allocates memory dynamically from system in case there is no available memory in the pool. A global internal counter monitors the memory usage of all http response data across all processes, new requests will not be cached if the counter exceeds data-size.

data-size

Determines the size of memory zone along with dict-size.

It accepts units like m, M, g and G. By default, the size is 1024 * 1024 bytes, which is also the minimal size.

dict-size

Determines the size of memory used by hash table.

It accepts units like m, M, g and G. By default, the size is 1024 * 1024 bytes, which is also the minimal size.

Note that it only decides the memory used by hash table buckets not keys. In fact, keys are stored in memory zone which is limited by data-size.

dict-size(number of buckets) is different from number of keys. New keys can still be added to hash table even if the number of keys exceeds dict-size(number of buckets) as long as there are enough memory.

Nevertheless it may lead to a potential performance drop if number of keys is greater than dict-size(number of buckets). An approximate number of keys multiplied by 8 (normally) as dict-size should be fine.

dict-size will be removed in future release, automatically resizing hash table in first version will be added back.

purge-method [cache only]

Define a customized HTTP method with max length of 14 to purge cache, it is PURGE by default.

uri [cache only]

Enable cache manager/stats API and define the endpoint:

nuster cache on uri /_my/_unique/_/_cache/_uri

By default, the cache manager/stats is disabled. When it is enabled, remember to restrict the access(see FAQ).

See Cache Management and Cache stats for details.

proxy: nuster cache|nosql

syntax:

nuster cache [on|off]

nuster nosql [on|off]

default: on

context: backend

Determines whether or not to use cache/nosql on this proxy, additional nuster rule should be defined. If there are filters on this proxy, put this directive after all other filters.

nuster rule

syntax: nuster rule name [key KEY] [ttl TTL] [code CODE] [if|unless condition]

default: none

context: backend

Define rule to specify cache/nosql creating conditions, properties. At least one rule should be defined.

nuster cache on

# cache request `/asdf` for 30 seconds
nuster rule asdf ttl 30 if { path /asdf }

# cache if the request path begins with /img/
nuster rule img if { path_beg /img/ }

# cache if the response header `cache` is `yes`
acl resHdrCache res.hdr(cache) yes
nuster rule r1 if resHdrCache

It is possible and recommended to declare multiple rules in the same section. The order is important because the matching process stops on the first match.

acl pathA path /a.html
nuster cache on
nuster rule all ttl 3600
nuster rule path01 ttl 60 if pathA

rule path01 will never match because first rule will cache everything.

name

Define a name for this rule.

It will be used in cache manager API, it does not have to be unique, but it might be a good idea to make it unique. Rules with same name are treated as one.

key KEY

Define the key for cache/nosql, it takes a string combined by following keywords with . separator:

• method: http method, GET/POST...
• scheme: http or https
• host: the host in the request
• uri: first slash to end of the url
• path: the URL path of the request
• delimiter: '?' if query exists otherwise empty
• query: the whole query string of the request
• header_NAME: the value of header NAME
• cookie_NAME: the value of cookie NAME
• param_NAME: the value of query NAME
• body: the body of the request

The default key of CACHE is method.scheme.host.uri, and default key of NoSQL is GET.scheme.host.uri.

Example

GET http://www.example.com/q?name=X&type=Y

http header:
GET /q?name=X&type=Y HTTP/1.1
Host: www.example.com
ASDF: Z
Cookie: logged_in=yes; user=nuster;

Should result:

• method: GET
• scheme: http
• host: www.example.com
• uri: /q?name=X&type=Y
• path: /q
• delimiter: ?
• query: name=X&type=Y
• header_ASDF: Z
• cookie_user: nuster
• param_type: Y
• body: (empty)

So default key produces GET.http.www.example.com./q?name=X&type=Y., and key method.scheme.host.path.header_ASDF.cookie_user.param_type produces GET.http.www.example.com./q.Z.nuster.Y..

If a request has the same key as a cached http response data, then cached data will be sent to the client.

ttl TTL

Set a TTL on key, after the TTL has expired, the key will be deleted.

It accepts units like d, h, m and s. Default ttl is 0 which does not expire the key.

code CODE1,CODE2...

Cache only if the response status code is CODE.

By default, only 200 response is cached. You can use all to cache all responses.

nuster rule only200
nuster rule 200and404 code 200,404
nuster rule all code all

if|unless condition

Define when to cache using HAProxy ACL.

The evaluation involves two stages: request stage and response stage.

Cache will be performed if:

1. The evaluation in request stage is true,
2. The evaluation in request stage is false but true in response stage.

Please be very careful if you use negation in the condition or samples not available in certain stage

For example,

1. Cache if the request path begins with /img/

   nuster rule img if { path_beg /img/ }

This will work because the evaluation in request stage will either be ture or false, and will never be true in response stage as path is not available in the response stage.

2. Cache if Content-Type in response is image/jpeg

   nuster rule jpeg if { res.hdr(Content-Type) image/jpeg }

This will work because the evaluation in request stage is always false as res.hdr is not available in the request stage, and will be either true or false in response stage.

3. Cache if the request path begins with /img/ and Content-Type in response is image/jpeg

It won't work if you define the rule as:

nuster rule img if { path_beg /img/ } { res.hdr(Content-Type) image/jpeg }

because path is not available in the response stage and res.hdr is not available in the request stage, so the evaluation will never be true.

In order the make this work, path needs to be allocated for further use in reponse stage:

http-request set-var(txn.pathImg) path
acl pathImg var(txn.pathImg) -m beg /img/
acl resHdrCT res.hdr(Content-Type) image/jpeg
nuster rule r3 if pathImg resHdrCT

4. Another example, cache if the request path does not begin with /api/

It won't work neither:

acl NoCache path_beg /api/
nuster rule r3 if !NoCache

Because the evaluation of NoCache against /api/ in request stage is true, and the negation is false, which is the desired state, but in response stage, the evaluation of NoCache is always false as path is not available in response stage, and it will be cached as the negation !NoCache is true.

This will work:

http-request set-var(txn.path) path
acl NoCache var(txn.path) -m beg /api/
nuster rule r1 if !NoCache

I will add several new sample fetch methods to simplify this kind of tasks in futrue versions.

See 7. Using ACLs and fetching samples section in HAProxy configuration

Cache

nuster can be used as an HTTP proxy cache server like Varnish or Nginx to cache dynamic and static HTTP response.

You can use HAProxy functionalities to terminate SSL, normalize HTTP, support HTTP2, rewrite the URL or modify headers and so on, and additional functionalities provided by nuster to control cache.

Cache Management

Cache can be managed via a manager API which endpoints is defined by uri and can be accessed by making HTTP requests along with some headers.

Eanble and define the endpoint

nuster cache on uri /nuster/cache

Basic usage

curl -X POST -H "X: Y" http://127.0.0.1/nuster/cache

REMEMBER to enable access restriction

Cache rule enable and disable

Rule can be disabled at run time through manager uri. Disabled rule will not be processed, nor will the cache created by that.

headers

header	value	description
state	enable	enable rule
	disable	disable rule
name	rule NAME	the rule to be enabled/disabled
	proxy NAME	all rules belong to proxy NAME
	*	all rules

Keep in mind that if name is not unique, all rules with that name will be disabled/enabled.

Examples

• Disable cache rule r1

  curl -X POST -H "name: r1" -H "state: disable" http://127.0.0.1/nuster/cache

• Disable all cache rule defined in proxy app1b

  curl -X POST -H "name: app1b" -H "state: disable" http://127.0.0.1/nuster/cache

• Enable all cache rule

  curl -X POST -H "name: *" -H "state: enable" http://127.0.0.1/nuster/cache

Cache TTL

Change the TTL. It only affects the TTL of the responses to be cached, does not update the TTL of existing caches.

headers

header	value	description
ttl	new TTL	see ttl in nuster rule
name	rule NAME	the cache rule to be changed
	proxy NAME	all cache rules belong to proxy NAME
	*	all cache rules

Examples

curl -X POST -H "name: r1" -H "ttl: 0" http://127.0.0.1/nuster/cache
curl -X POST -H "name: r2" -H "ttl: 2h" http://127.0.0.1/nuster/cache

Update state and TTL

state and ttl can be updated at the same time

curl -X POST -H "name: r1" -H "ttl: 0" -H "state: enabled" http://127.0.0.1/nuster/cache

Cache Purging

There are several ways to purge cache by making HTTP PURGE requests to the manager uri defined by uri.

You can define customized http method using purge-method MYPURGE other than the default PURGE in case you need to forward PURGE to backend servers.

Purge one specific url

This method deletes the specific url that is being requested, like this:

curl -XPURGE https://127.0.0.1/imgs/test.jpg

It creates a key of GET.scheme.host.uri, and deletes the cache with that key.

Note by default cache key contains Host, if you cache a request like http://example.com/test and purge from localhost you need to specify Host header:

curl -XPURGE -H "Host: example.com" http://127.0.0.1/test

Purge by name

Cache can be purged by making HTTP PURGE(or purge-method) requests to the manager uri along with a name HEADER.

headers

header	value	description
name	nuster rule NAME	caches belong to rule ${NAME} will be purged
	proxy NAME	caches belong to proxy ${NAME}
	*	all caches

Examples

# purge all caches
curl -X PURGE -H "name: *" http://127.0.0.1/nuster/cache
# purge all caches belong to proxy applb
curl -X PURGE -H "name: app1b" http://127.0.0.1/nuster/cache
# purge all caches belong to rule r1
curl -X PURGE -H "name: r1" http://127.0.0.1/nuster/cache

Purge by host

You can also purge cache by host, all caches belong to that host will be deleted:

headers

header	value	description
x-host	HOST	the ${HOST}

Examples

curl -X PURGE -H "x-host: 127.0.0.1:8080" http://127.0.0.1/nuster/cache

Purge by path

By default, the query part is also used as cache key, so there will be multiple caches if the query differs.

For example, for cache rule nuster rule imgs if { path_beg /imgs/ }, and request

curl https://127.0.0.1/imgs/test.jpg?w=120&h=120
curl https://127.0.0.1/imgs/test.jpg?w=180&h=180

There will be two cache objects since the default key contains query part.

In order to delete that, you can

delete one by one in case you know all queries

curl -XPURGE https://127.0.0.1/imgs/test.jpg?w=120&h=120
curl -XPURGE https://127.0.0.1/imgs/test.jpg?w=180&h=180

It does not work if you don't know all queries.

use a customized key and delete once in case that the query part is irrelevant

Define a key like nuster rule imgs key method.scheme.host.path if { path_beg /imgs }, in this way only one cache will be created, and you can purge without query:

curl -XPURGE https://127.0.0.1/imgs/test.jpg

It does not work if the query part is required.

delete by rule NAME

curl -X PURGE -H "name: imgs" http://127.0.0.1/nuster/cache

It does not work if the nuster rule is defined something like nuster rule static if { path_beg /imgs/ /css/ }.

This method provides a way to purge just by path:

headers

header	value	description
path	PATH	caches with ${PATH} will be purged
x-host	HOST	and host is ${HOST}

Examples

#delete all caches which path is /imgs/test.jpg
curl -X PURGE -H "path: /imgs/test.jpg" http://127.0.0.1/nuster/cache
#delete all caches which path is /imgs/test.jpg and belongs to 127.0.0.1:8080
curl -X PURGE -H "path: /imgs/test.jpg" -H "x-host: 127.0.0.1:8080" http://127.0.0.1/nuster/cache

Purge by regex

You can also purge cache by regex, the caches which path match the regex will be deleted.

headers

header	value	description
regex	REGEX	caches which path match with ${REGEX} will be purged
x-host	HOST	and host is ${HOST}

Examples

#delete all caches which path starts with /imgs and ends with .jpg
curl -X PURGE -H "regex: ^/imgs/.*\.jpg$" http://127.0.0.1/nuster/cache
#delete all caches which path starts with /imgs and ends with .jpg and belongs to 127.0.0.1:8080
curl -X PURGE -H "regex: ^/imgs/.*\.jpg$" -H "127.0.0.1:8080" http://127.0.0.1/nuster/cache

PURGE CAUTION

1. ENABLE ACCESS RESTRICTION

2. If there are mixed headers, use the precedence of name, path & host, path, regex & host, regex, host

   curl -XPURGE -H "name: rule1" -H "path: /imgs/a.jpg": purge by name

3. If there are redundant headers, use the first occurrence

   curl -XPURGE -H "name: rule1" -H "name: rule2": purge by rule1

4. regex is NOT glob

   For example, all jpg files under /imgs should be ^/imgs/.*\.jpg$ instead of /imgs/*.jpg

Cache Stats

Cache stats can be accessed by making HTTP GET request to the endpoint defined by uri;

Eanble and define the endpoint

nuster cache on uri /nuster/cache

Usage

curl http://127.0.0.1/nuster/cache

Output

• used_mem: The memory used for response, not include overheads.
• req_total: Total request number handled by cache enabled backends, not include the requests handled by backends without cache enabled
• req_hit: Number of requests handled by cache
• req_fetch: Fetched from backends
• req_abort: Aborted when fetching from backends

Others are very straightforward.

NoSQL

nuster can be used as a RESTful NoSQL cache server, using HTTP POST/GET/DELETE to set/get/delete Key/Value object.

Basic Operations

Set

curl -v -X POST -d value1 http://127.0.0.1:8080/key1
curl -v -X POST --data-binary @icon.jpg http://127.0.0.1:8080/imgs/icon.jpg

Get

curl -v http://127.0.0.1:8080/key1

Delete

curl -v -X DELETE http://127.0.0.1:8080/key1

Response

Check status code.

• 200 OK
  • POST/GET: succeeds
  • DELETE: always
• 400 Bad request
  • empty value
  • incorrect acl, rules, etc
• 404 Not Found
  • POST: failed on all rule tests
  • GET: not found
• 405 Method Not Allowed
  • other methods
• 500 Internal Server Error
  • any error occurs
• 507 Insufficient Storage
  • exceeds max data-size

Per-user data

By using header or cookie in key, you can save per-user data to same endpoint.

nuster rule r1 key method.scheme.host.uri.header_userId if { path /mypoint }
nuster rule r2 key method.scheme.host.uri.cookie_sessionId if { path /mydata }

Set

curl -v -X POST -d "333" -H "userId: 1000" http://127.0.0.1:8080/mypoint
curl -v -X POST -d "555" -H "userId: 1001" http://127.0.0.1:8080/mypoint

curl -v -X POST -d "userA data" --cookie "sessionId=ijsf023xe" http://127.0.0.1:8080/mydata
curl -v -X POST -d "userB data" --cookie "sessionId=rosre329x" http://127.0.0.1:8080/mydata

Get

curl -v http://127.0.0.1:8080/mypoint
< 404 Not Found

curl -v -H "userId: 1000" http://127.0.0.1:8080/mypoint
< 200 OK
333

curl -v --cookie "sessionId=ijsf023xe" http://127.0.0.1:8080/mydata
< 200 OK
userA data

Clients

You can use any tools or libs which support HTTP: curl, postman, python requests, go net/http, etc.

FAQ

How to debug?

Set debug in global section, or start nuster with -d.

Cache related debug messages start with [CACHE].

How to cache POST request?

Enable option http-buffer-request and set body in cache rule key.

By default, the cache key does not include the body of the request, remember to put body in key field.

Note that the size of the request body must be smaller than tune.bufsize - tune.maxrewrite - request_header_size, which by default is 16384 - 1024 - request_header_size.

Refer to option http-buffer-request and tune.bufsize section in HAProxy configuration for details.

Also it might be a good idea to put it separately in a dedicated backend as example does.

How to restrict access?

You can use the powerful HAProxy acl, something like this

acl network_allowed src 127.0.0.1
acl purge_method method PURGE
http-request deny if purge_method !network_allowed

How to enable HTTP2

bind :443 ssl crt pub.pem alpn h2,http/1.1

Example

global
    nuster cache on data-size 100m
    nuster nosql on data-size 100m
    #daemon
    ## to debug cache
    #debug
defaults
    retries 3
    option redispatch
    timeout client  30s
    timeout connect 30s
    timeout server  30s
frontend web1
    bind *:8080
    mode http
    acl pathPost path /search
    use_backend app1a if pathPost
    default_backend app1b
backend app1a
    balance roundrobin
    # mode must be http
    mode http

    # http-buffer-request must be enabled to cache post request
    option http-buffer-request

    acl pathPost path /search

    # enable cache for this proxy
    nuster cache

    # cache /search for 120 seconds. Only works when POST/PUT
    nuster rule rpost key method.scheme.host.uri.body ttl 120 if pathPost

    server s1 10.0.0.10:8080
backend app1b
    balance     roundrobin
    mode http

    nuster cache on

    # cache /a.jpg, not expire
    acl pathA path /a.jpg
    nuster rule r1 ttl 0 if pathA

    # cache /mypage, key contains cookie[userId], so it will be cached per user
    acl pathB path /mypage
    nuster rule r2 key method.scheme.host.path.delimiter.query.cookie_userId ttl 60 if pathB

    # cache /a.html if response's header[cache] is yes
    http-request set-var(txn.pathC) path
    acl pathC var(txn.pathC) -m str /a.html
    acl resHdrCache1 res.hdr(cache) yes
    nuster rule r3 if pathC resHdrCache1

    # cache /heavy for 100 seconds if be_conn greater than 10
    acl heavypage path /heavy
    acl tooFast be_conn ge 100
    nuster rule heavy ttl 100 if heavypage tooFast

    # cache all if response's header[asdf] is fdsa
    acl resHdrCache2 res.hdr(asdf)  fdsa
    nuster rule resCache ttl 0 if resHdrCache1

    server s1 10.0.0.10:8080

frontend web2
    bind *:8081
    mode http
    default_backend app2
backend app2
    balance     roundrobin
    mode http

    # disable cache on this proxy
    nuster cache off
    nuster rule all

    server s2 10.0.0.11:8080

frontend nosql_fe
    bind *:9090
    default_backend nosql_be
backend nosql_be
    nuster nosql on
    nuster rule r1 ttl 3600

Conventions

1. Files with same name: those with .md extension belong to nuster, otherwise HAProxy

Contributing

• Join the development
• Give feedback
• Report issues
• Send pull requests
• Spread nuster

License

Copyright (C) 2017-2019, Jiang Wenyuan, < koubunen AT gmail DOT com >

All rights reserved.

Licensed under GPL, the same as HAProxy

HAProxy and other sources license notices: see relevant individual files.